June 14, 1993|By Sandra Blakeslee | Sandra Blakeslee,New York Times News Service

LAS VEGAS, Nev. -- In what doctors termed the most important discovery for diabetics since insulin, researchers said yesterday that the devastating complications of the disease could be prevented or delayed.

They said this is possible when diabetics closely monitor their blood sugar levels with a special meter throughout the day and inject themselves with insulin four to seven times daily to keep their blood sugar at a near-normal level.

In current practice, patients do not monitor their blood so closely and give themselves one or two doses of insulin a day, which causes their blood sugar to vary greatly.

An estimated 14 million Americans have diabetes, the researchers said, and each year tens of thousands of them go blind, lose their kidneys or have feet amputated because of the disease.

Most will probably now be advised to follow this new regimen, which may not only lengthen their lives and lessen their symptoms but also reduce the nation's health care costs. Even though patients may pay more in routine treatment each year, the long-term costs for complications and major related ailments will be significantly reduced, the researchers said.

The findings are from a research project reported in Las Vegas yesterday at the annual meeting of the American Diabetes Association.

Financed by the National Institute of Diabetes and Digestive and Kidney Diseases, the project "is the largest and most important study carried out in the history of diabetes," said the institute's director, Dr. Phillip Gorden. "It has major implications for the nation's health care system."

"The discovery of insulin was an absolute miracle," Dr. Gorden said. "This study is in the ball park of comparison."

The project, the Diabetes Control and Complications Trial, provides the first demonstration that diabetics can alter the course of their disease by keeping their blood sugar levels near normal, but the new regimen is not without its own perils, doctors said.

Diabetics who follow it have a threefold higher risk of passing out from low blood sugar, and therefore risk injuring themselves or others if they are driving or operating dangerous equipment, they said.

The study compared two types of treatment. In one, diabetics followed the conventional method. In the other, patients took burdensome steps to monitor and control their blood sugar. In doing so, the second group reduced the onset of serious complications by an average of 50 percent to 60 percent. Some were even able to reverse mild kidney disease.

The benefits were so striking that officials stopped the trial one year early so the findings could be announced and all diabetics could benefit from the findings, Dr. Gorden said.

"It is extraordinarily exciting," said Dr. David M. Nathan, an associate professor of medicine at Harvard Medical School and a principal investigator in the trial. "This kind of thing comes along once in a lifetime."

Dr. Xavier Pi-Sunyer, president of the American Diabetes Association, added:

"The blood glucose level achieved in the intensively treated group in the trial should be the new standard of care. Although tight control is not for everyone, the goal for most people with diabetes should be to achieve blood glucose levels as close to normal as possible."

The findings will generate a windfall for manufacturers of medical devices, but could save the nation money in the long run, Dr. Pi-Sunyer said. The tight control method roughly doubles the $1,500 to $2,000 annual cost of treating each diabetic, he said.

But he added that the overall cost may turn out far lower than the $20 billion spent each year directly treating diabetic complications.

Diabetes is a disorder of metabolism. During digestion, food is broken down into sugar, which passes into the bloodstream. To thrive and grow, cells absorb sugar with the help of the hormone insulin, produced by the pancreas. People without diabetes produce exactly the right amount of insulin to keep blood sugar at optimum levels.

But an estimated 1.4 million Americans produce no insulin whatsoever because their own immune systems have mysteriously destroyed the insulin-producing beta cells of the pancreas. They require daily insulin injections to treat their form of the disease, which is called Type 1 diabetes.

Another 13 million Americans make insulin but their bodies do not use it effectively. Sugar builds up in their bloodstreams, causing Type 2 diabetes, which is usually treated through diet, exercise, drugs or, in a third of cases, with insulin injections.

Researchers examined patients regularly for signs of diabetic complications and were stunned by the results.

Tight control reduced the risk of developing eye disease by 76 percent. After glaucoma, diabetes is the leading cause of new cases of blindness among adults.

The intensive regimen reduced the risk of developing minor kidney disease by 35 percent and more overt kidney disease by 56 percent. Diabetes is the leading cause of kidney failure in the United States.

Although the data are still being analyzed, there are hints that tight control may reverse mild kidney damage in some patients, Dr. Nathan said.

Finally, the treatment reduced nerve damage by 60 percent. About 25,000 diabetics have their feet amputated each year due to such nerve complications.

Although the trial was conducted on patients with Type 1 diabetes, the findings are expected to benefit people with Type 2 diabetes as well, the doctors said. Research suggests that complications arising from both forms of the disease occur for similar reasons.